for some fixed \(R \geqslant 0\) , so that quantities bounded by an arbitrarily small power of \(\eta ^{-1}\)  or \(|A|\)  are also \(\ll B^{\epsilon }\)  for any \(\epsilon >0\) . If these assumptions do not hold, then the statement of Theorem REF  is trivial. Employing the machinery from [1]}, we have
\(N_{w,\mathbf {a}}(B) = \frac{C_Q}{Q^2}\sum _{\mathbf {c}\in \mathbb {Z}^4}\sum _{q=1}^{\infty }q^{-4}S_{q,\mathbf {a}}(\mathbf {c})I_{q,\mathbf {a}}(\mathbf {c}),\) 
